It is an object of the present invention to provide a novel medicament for preventing and/or treating ophthalmologic diseases caused by ocular angiogenesis. According to the present invention, provided is a medicament for preventing and/or treating ophthalmologic diseases caused by ocular angiogenesis, which comprises, as an active ingredient, a pyrazolone derivative such as 3-methyl-1-phenyl-2-pyrazolin-5-one, or a physiologically acceptable salt thereof, or a hydrate thereof or a solvate thereof.
